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Biomedical subjects

P Shearer

Publications and source records attributed to P Shearer.

12 recordsLinked to original sources
PubMed2001

Treatment with nephrectomy only for small, stage I/favorable histology Wilms' tumor: a report from the National Wilms' Tumor Study Group.

PURPOSE: Children younger than 24 months with small (< 550 g), favorable histology (FH) Wilms tumors (WTs) were shown in a pilot study to have an excellent prognosis when treated with nephrectomy only. PATIENTS AND METHODS: A study of nephrectomy only for the treatment of selected children with FH WT was undertaken. Stringent stopping rules were designed to insure closure of the study if the true 2-year relapse-free survival rate was 90% or lower. RESULTS: Seventy-five previously untreated children younger than 24 months with stage I/FH WTs for which the surgical specimen weighed less than 550 g were treated with nephrectomy only. Three patients developed metachronous, contralateral WT 1.1, 1.4, and 2.3 years after nephrectomy, and eight patients relapsed 0.3 to 1.05 years after diagnosis (median, 0.4 years; mean, 0.51 years). The sites of relapse were lung (n = 5) and operative bed (n = 3). The 2-year disease-free (relapse and metachronous contralateral WT) survival rate was 86.5%. The 2-year survival rate is 100% with a median follow-up of 2.84 years. The 2-year disease-free survival rate (excluding metachronous contralateral WT) was 89.2%, and the 2-year cumulative risk of metachronous contralateral WT was 3.1%. CONCLUSION: Children younger than 24 months treated with nephrectomy only for a stage I/FH WT that weighed less than 550 g had a risk of relapse, including the development of metachronous contralateral WT, of 13.5% 2 years after diagnosis. All patients who experienced relapse on this trial are alive at this time. This approach will be re-evaluated in a clinical trial using a less conservative stopping rule.

Disease-Free Survival↗
PubMed2001

Secondary acute myelogenous leukemia in patients previously treated for childhood renal tumors: a report from the National Wilms Tumor Study Group.

PURPOSE: This review characterized cases of secondary acute myelogenous leukemia (AML) occurring after treatment of renal neoplasms on protocols of the National Wilms Tumor Study Group (NWTSG) between October 1969 and December 1991. PATIENTS AND METHODS: The NWTSG database was reviewed for cases of secondary AML and for WT1 status of the affected patients. Referring institutions were contacted by a confidential letter requesting pathology reports, results of immunophenotyping, cytogenetic, and molecular analyses, and details concerning treatment of AML. RESULTS: Of the 5,278 patients treated during the study period, 43 had second malignant neoplasms, and 7 of these 43 had AML. At the time of diagnosis of Wilms tumor, the median age of the seven patients (4 boys) was 3.2 years. Five of the seven renal neoplasms had favorable histologic characteristics. The most common French-American-British morphology was M5. One patient had bilateral tumors, and two were treated for recurrent Wilms tumor. All patients received chemotherapy regimens that included doxorubicin (6) or etoposide (1), and six were treated with infradiaphragmatic irradiation. The median latency period from initial diagnosis of the renal neoplasm to development of secondary AML was 3 years (range, 1.2-4 yrs). One patient had the translocation t(9:11)(p22;q23); WT1 status was not noted for any of the seven patients. CONCLUSIONS: The development of secondary AML in this subset of patients after treatment of renal neoplasms may reflect the interaction of the effects of treatment and possible genetic predisposition toward cancer.

Abnormalities, Multiple↗
PubMed2000

Late effects of treatment in survivors of childhood acute myeloid leukemia.

PURPOSE: To investigate the incidence of and risk factors for late sequelae of treatment in patients who survived for more than 10 years after the diagnosis of childhood acute myeloid leukemia (AML). PATIENTS AND METHODS: Of 77 survivors (median follow-up duration, 16. 7 years), 44 (group A) had received chemotherapy, 18 (group B) had received chemotherapy and cranial irradiation, and 15 (group C) had received chemotherapy, total-body irradiation, and allogeneic bone marrow transplantation. Late complications, tobacco use, and health insurance status were assessed. RESULTS: Growth abnormalities were found in 51% of survivors, neurocognitive abnormalities in 30%, transfusion-acquired hepatitis in 28%, endocrine abnormalities in 16%, cataracts in 12%, and cardiac abnormalities in 8%. Younger age at the time of diagnosis or initiation of radiation therapy, higher dose of radiation, and treatment in groups B and C were risk factors for the development of academic difficulties and greater decrease in height Z: score. In addition, treatment in group C was a risk factor for a greater decrease in weight Z: score and the development of growth-hormone deficiency, hypothyroidism, hypogonadism, infertility, and cataracts. The estimated cumulative risk of a second malignancy at 20 years after diagnosis was 1.8% (95% confidence interval, 0.3% to 11.8%). Twenty-two patients (29%) were smokers, and 11 (14%) had no medical insurance at the time of last follow-up. CONCLUSION: Late sequelae are common in long-term survivors of childhood AML. Our findings should be useful in defining areas for surveillance of and intervention for late sequelae and in assessing the risk of individual late effects on the basis of age and history of treatment.

Acute Disease↗
PubMed2000

Improving the selective use of plain radiographs in the initial evaluation of shoulder pain.

OBJECTIVE: In a previous retrospective study, we had found that shoulder radiographs were overused in the initial evaluation of patients presenting to the emergency department with shoulder pain. Our objective was to prospectively define clinical criteria that identify patients who have a low risk of radiographic findings that influence the management of the initial evaluation of shoulder pain in the emergency department. METHODS: All adult patients presenting to the emergency department of a university teaching hospital with shoulder pain were eligible to participate. Patients with deformities, penetrating wounds, referred pain, and those presenting for followup were excluded. Data were recorded prospectively using a standardized form. All radiographs were classified as therapeutically uninformative (TU) except fracture, acromioclavicular joint separation (> or =Grade 3), infection, or malignancy. A classification tree was used for analysis. RESULTS: Two hundred six patients had shoulder radiographs, of which 88% were TU. The model yielded 3 sets of low risk patients with a high percentage of TU radiographs: (1) no fall, no swelling (99% TU: 106 TU, 1 radiograph with lytic lesions in a cancer patient); (2) a fall, but no swelling, and no pain at rest (100% TU, n = 18); (3) a fall and pain at rest, but no swelling and normal range of motion (100% TU, n = 10). Not performing radiographs on these low risk patients would have decreased radiograph utilization from 52 to 18% of all shoulder patients seen. CONCLUSION: Our findings suggest that specific clinical criteria are able to identify patients who do not need radiographs as part of the initial management of shoulder pain. Prospective validation of these criteria are needed to confirm that these low risk patients can be safely evaluated without radiographs.

Adult↗
PubMed1997

A pilot study of continuous infusion Ara-C in combination with rhG-CSF in relapsed childhood acute myeloid leukemia.

Relapse in acute myeloid leukemia (AML) following intensive chemotherapy bears a bad prognosis. We treated 18 children with relapsed AML on two separate protocols that included continuous infusion (CI) of cytosine arabinoside (ara-C) (total dose 4gr-6gr/m2) over 96-120 hours. In an attempt to increase the fraction of blasts in S-phase and render them more sensitive to cell-cycle specific agents such as ara-C, 10 patients received 5mcg/kg rhG-CSF twice daily beginning 48 hours before and continuing through the duration of the CI ara-C (POG #9192 study). The percentage of cells is S phase before and after G-CSF administration was determined. In a second group of patients (n = 8) who received ara-C alone, endogenous concentrations of G-CSF and serial blood counts were measured (St Jude's R4 study). The rationale of the St Jude's R4 was to optimize the schedule of the second course of ara-C at a time when the patient's endogenous G-CSF concentration was increased and thus maximize the percent of cells captured in S phase. Four out of 8 patients receiving CI ara-C alone and 4 out of 10 patients receiving CI ara-C with rhG-CSF achieved a complete remission (CR) after 1 cycle of therapy. Four patients in CR underwent marrow transplantation (2 allogeneic and 2 autologous). Cell cycle analysis of blast cells cultured in vitro with or without G-CSF showed a two fold increase in the percentage of cells in S phase (P = 0.03) whereas cells obtained from patients before and after G-CSF administration showed no difference in cell cycling. Correlation between G-CSF concentrations and ANC showed a negative association indicating that the regulatory mechanisms for G-CSF production remained intact. In our relatively small series, CI ara-C achieved a CR rate of 44% with rhG-CSF having no effect on the remission rate. Although in vitro rhG-CSF increased the percentage of blasts in S phase significantly, in vivo effects were not observed. Larger studies with combinations of different hematopoietic growth factors and cell-cycle active drugs are needed to evaluate the role of these cytokines in the therapy of recurrent AML.

Acute Disease↗
PubMed1996

Identification of novel regions of deletion in familial Wilms' tumor by comparative genomic hybridization.

Wilms' tumor, an embryonic renal neoplasm diagnosed primarily in young children, can occur in either a noninheritable (sporadic) or a familial form, with the latter presenting earlier and more often at bilateral sites. Although familial Wilms' tumor is thought to develop through inherited and acquired mutational inactivation of the two alleles of predisposing tumor suppressor genes, only a small percentage of cases can be accounted for by mutations affecting the WT1 gene or linkage to the Beckwith-Weidemann syndrome of the BWS region on the short arm of chromosome 11. To find chromosomal regions that might contain genes important in the development of this disease, we used comparative genomic hybridization to analyze tumor specimens from familial cases for chromosomal regions that were consistently lost. Although inherited lesions of tumor suppressors are most often inactivating point mutations, accompanying somatic lesions in the malignant clones are often chromosomal deletions; therefore, consensus regions of loss in familial tumors are likely to harbor genes linked to familial predisposition. There were extensive genomic aberrations among the eight familial cases studied, with an average of 6.5 changes/tumor (range, 0-22). The most consistent findings with likely biological relevance were deletions of chromosomes 4 (consensus, 4q21-qter), 9 (consensus, 9p21-pter), 20p, and 3 (consensus, 3q12-q21). These regions have not been previously implicated in Wilms' tumor and may harbor novel genes that could aid attempts to understand the familial predisposition as well as the development and progression of these tumors.

Chromosome Deletion↗
PubMed1996

Epithelioid sarcoma in children.

Literature regarding the natural history and prognosis of epithelioid sarcoma in the pediatric population is sparse. During the past 11 years, eight patients with epithelioid sarcoma were treated at St Jude Children's Research Hospital. Of the eight children, six of whom were male, seven presented with localized disease and one with metastatic disease. The primary tumor was located in the upper extremity in four patients; the other sites were the scalp, external ear, back, and mediastinum. The mean duration of symptoms before diagnosis was 8.3 months (range, 1 to 12 months). Surgical treatment comprising amputation or wide local excision was performed in six patients, three of whom had additional lymph node dissection. Three patients received multiagent chemotherapy, and four patients were treated with supplementary radiation. Two patients died of progressive local and distant disease within 9 months of diagnosis. The other six patients are alive and have no evidence of disease 12 months to 10 years 6 months after the completion of treatment.

Adolescent↗
PubMed1994

Pulmonary insufficiency complicating therapy with high dose cytosine arabinoside in five pediatric patients with relapsed acute myelogenous leukemia.

BACKGROUND: The occurrence of fatal or nearly fatal pulmonary insufficiency in 5 of 22 pediatric patients with relapsed acute myelogenous leukemia (AML) treated with high dose cytosine arabinoside (Ara-C) at St. Jude Children's Research Hospital, Memphis, Tennessee, and institutions affiliated with the Pediatric Oncology Group (POG) is reported. METHODS: Cytosine arabinoside (1.0-1.5 g/m2/day) was given as a 5-day continuous infusion to all patients. Four patients with persistent leukemia received a second 3- or 5-day course. The POG protocol included the administration of granulocyte colony stimulating factor for the priming of myeloblasts. Diagnostic criteria for pulmonary insufficiency included noncardiogenic pulmonary edema with exclusion of underlying cardiorespiratory, infectious, or metabolic conditions. Autopsy material also was reviewed. RESULTS: Of the 22 patients 5 died (23%), including 2 who received a second course of Ara-C as a result of pulmonary insufficiency that developed at a median of 8 days (range, 3-38 days) after the first course. Three patients died despite intubation and pressor support. Two patients were managed successfully with colloids, diuresis, and oxygen by face mask; remission was achieved in both. The postmortem examination of one patient disclosed airless lungs, profound pulmonary edema, and subpleural nodules, but no evidence of leukemia. CONCLUSION: Pulmonary insufficiency from high dose Ara-C varies in severity and may be fatal. It may occur during or after treatment. Awareness of this potential complication, careful attention to fluid status, and aggressive supportive care may optimize outcome.

Acute Disease↗
PubMed1994

Neurofibromatosis type I and malignancy: review of 32 pediatric cases treated at a single institution.

Thirty-two cases of neurofibromatosis Type I (NF1) were identified among 6,678 pediatric cancer patients treated at St. Jude Children's Research Hospital over a 29-year period. A total of 35 malignant neoplasms have been diagnosed in these patients. Two of three patients with second malignant neoplasms had colon cancer at the primary or second tumor. Of particular interest are two cases in which both NF1 and malignant peripheral nerve sheath tumors were present in multiple successive generations: a patient with colon cancer and non-Hodgkin lymphoma who has a constitutional abnormality of the p53 gene, and a patient with acute lymphoblastic leukemia with the Philadelphia chromosome and other cytogenetic abnormalities, including the t(8;14). Outcome of patients in the largest subgroup, that of malignant peripheral nerve sheath tumors, was favorable only for those patients having resectable extremity lesions. In contrast, all patients with central nervous system tumors are surviving. These cases reflect the molecular and cytogenetic abnormalities that can be present in NF1 and the variety of tumors that may result in these patients.

Adolescent↗
PubMed1993

Bilateral Wilms tumor. Review of outcome, associated abnormalities, and late effects in 36 pediatric patients treated at a single institution.

BACKGROUND: Patients with bilateral Wilms tumor have an increased incidence of associated abnormalities and nephrogenic rests and require individualized multimodality therapy for cure. The authors reported the associated abnormalities, outcome, complications, and late effects of treatment in a group of children with bilateral Wilms tumor treated at St. Jude Children's Research Hospital, Memphis, Tennessee, over a 28-year period. METHODS: The records of 36 consecutive pediatric patients diagnosed with bilateral Wilms tumor between 1962-1990 were analyzed. Biopsy material was also reviewed, with particular emphasis on characterization of nephrogenic rests and histology. RESULTS: Twenty-nine patients had synchronous tumors and 7 had metachronous lesions. Associated physical abnormalities were present in 12 patients and involved the genitourinary, cardiovascular, integumentary, and musculoskeletal systems. The overall survival for patients with metachronous tumors (71%) was similar to that for those with synchronous tumors (70%). There was no effect of age or the presence of nephroblastomatosis. Two patients with synchronous tumors initially treated with nephrectomy eventually required bilateral nephrectomies for contralateral recurrence after chemotherapy and radiation therapy. Nephrogenic rests were present in 22 of 30 evaluable patients. Two of three patients with metachronous tumors had intralobar nephrogenic rests. Bilateral renal salvage procedures were demonstrated to be technically feasible and effective in controlling disease without compromising renal function or survival. Late effects included scoliosis in three patients treated before 1970, cardiomyopathy in one patient who received 300 mg/m2 doxorubicin and 12 Gy pulmonary irradiation, and benign tumors in two patients, one of whom also had a bowel obstruction. Serum creatinine, urea nitrogen, and blood pressure were normal in 23 of 26 survivors. CONCLUSIONS: The authors' experience supports a favorable outcome with minimal late effects for patients with bilateral Wilms tumor who receive individualized therapy at pediatric oncology centers.

Child↗